Various methods of orthodontic treatment have been used to effect advancement of the mandible. The methods can be broken down into two categories: those using removable appliances and those using fixed appliances.
Removable appliances are often popular with patients due to controllable and limited wear time while still achieving good results. However, such treatment also includes the risks associated with failure of patient compliance. A patient's inability or unwillingness to wear an appliance for the prescribed period of time may lengthen treatment time or compromise the results achieved. Further, orthodontists often disfavor the use of removable appliances because of a patient's failure to cooperate or because the continuous removal and replacement of an appliance necessitates constant adjustment. Fixed appliances, though often popular among orthodontists because of reduced treatment time and better results, are often disfavored by patients. This is particularly true of the prior art fixed mandibular advancement devices. They are generally anchored to the teeth in the upper first molar buccal area and lower first bicuspid or cuspid buccal area with bulky connecting arms designed for advancement of the mandible. Such bulky appliances are not aesthetically pleasing and in some cases cause considerable discomfort. This may lead to patient rejection or non-acceptance of the appliance.
One prior art mandibular advancement device is the Herbst appliance. Briefly, the Herbst appliance and its modified versions include a central positioning rod operatively disposed between the upper and lower dental arches and anchored at opposite ends to bands or other framework on the teeth. The appliance is designed to advance the mandible or effect other jaw movements. The central positioning rod is relatively bulky to provide structural integrity. The overall device is made more bulky due to the connecting arms designed to secure the central positioning rod at opposing ends to the bands on the teeth. The connecting arms secure the central rod in place and allow hinged movement for opening and closing of the jaw. Each connecting arm comprises a separate securing element, such as a screw, to attach the central positioning rod to bands on the teeth. The screw is inserted through an eyelet in the rod and affixed to the band. The screw, thus secures the rod in place and also allows pivoting of the rod when the jaw is opened and closed. This device is bulky, is not aesthetically pleasing and is not comfortable to wear.
Another device used for effecting jaw movements is known as the Jasper Jumper and is essentially described in U.S. Pat. No. 4,708,646. The appliance includes a central positioning spring which is operatively connected at its opposing ends to the opposing dental arches. The device is affixed to bands or brackets on a patient's teeth by separate attachment components such as hook and eyelet means. The spring creates a continuous force, and the attachment components additionally allow for the opening and closing of a patient's jaw. This device includes several separate pieces and is also bulky within a patient's mouth creating patient discomfort.